Biggest patent holder can't get as many investors to pony up any more.

Most "patent trolls" are small operations with just a few real employees. Intellectual Ventures (IV) isn't like that; it has 700 employees and tens of thousands of patents. For years, IV just amassed patents and issued threats, but in 2010 it started filing infringement lawsuits. Since then, it has filed 52 patent lawsuits, according to Reuters.

Apparently it isn't that easy to keep hundreds of employees on the payroll with large-scale litigation. Reuters and various other news outlets have reported that the king of all patent-holders is letting go of almost 20 percent of its employees, or about 140 workers. It's the second round of layoffs at IV this year, following a five percent cutback in February.

Critics who complain about patent trolls have pointed to IV as being the most alarming threat of all. For its part, IV says it's creating a "market for invention," allowing inventors to reap cash from their ideas.

IV's co-founder and CTO, Edward Jung, says the company is pleased with its returns. The layoffs are just part of the company's natural evolution, he explained to BloombergBusinessweek:

IV was the first company to try to amass so many patents, and it had to hire hundreds of people to invent the processes for buying ideas in bulk. People were needed to sort through patents, acquire them covertly, think up complementary ideas, and deal with the associated paperwork. “We have more data than anybody and have analyzed it over the years,” Jung says. “Our analysis has allowed us to save a lot of needless paperwork and become more efficient. We don’t need as many people to sift through and sort information now.” Much of the work has been simplified and automated.

Over the years, IV has raised around $6 billion to buy patents. It began a second round of fundraising last year, but it hasn't seen as much participation as it hoped for. Companies like Google, Apple, and Intel, who invested in IV when it presented itself as a kind of "patent defense fund," are no longer are willing to invest.

IV took its first patent lawsuit to trial against Google-owned Motorola Mobility in February, but it ended in a mistrial. Two months later, IV's case against Capital One was thrown out just before trial.